Hybrid gas circuit breakers generally refer to circuit breakers assembled with disconnect switches, ground switches and bushings as a complete assembly. Conventional air substations have disconnect switches as a separate assembly from a circuit breaker and grounding is accomplished manually. In contrast, a hybrid circuit breaker is a complete assembly consisting of a gas insulated circuit breaker with disconnect switches, ground switches, and bushings in gas insulated equipment. Compared to a conventional air insulated assembly, the hybrid circuit breaker greatly reduces the space requirement for such assemblies. The reduced size can also be beneficial when space is not available for an air substation, but cost and/or other factors preclude utilization of a gas-insulated switchgear system.
A conventional hybrid circuit breaker is generally configured as a standard circuit breaker with the disconnect switches mounted on a breaker in place of the bushings, with the bushings and current transformers assembled above the disconnect switches. This results in an assembly with excessive height typically requiring shipping as separate components and assembly in the field, and with a final assembly that has mechanical devices at inaccessible heights. Assembly of components in the field requires complete testing of the final assembly including high voltage tests, leak tests, and mechanical tests.
Thus, it is desirable to provide improved systems and methods that facilitate shipping and final assembly of hybrid circuit breakers.